How to get the HttpServletResponse in Struts 2

In Struts 2 , you can use the following methods to get the HttpServletResponse object.

1. ServletActionContext

Access the HttpServletResponse via ServletActionContext class.

package com.mkyong.common.action;
 
import javax.servlet.http.HttpServletResponse;
import org.apache.struts2.ServletActionContext;
 
public class LocaleAction{
	//business logic
	public String execute() {
		HttpServletResponse response = ServletActionContext.getResponse();
 
		return "SUCCESS";
	}
}

2. ServletRequestAware

Access the HttpServletResponse by implementing the ServletResponseAware interface and override the setServletResponse() method.

When Struts 2 ‘servlet-config’ interceptor is seeing that an Action class is implemented the ServletResponseAware interface, it will pass a HttpServletResponse reference to the requested Action class via the setServletResponse() menthod. Of course, you can create a handy getServletResponse() to get the HttpServletResponse easily.

package com.mkyong.common.action;
 
import java.util.Locale;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts2.interceptor.ServletResponseAware;
 
public class LocaleAction implements ServletResponseAware{
 
	HttpServletResponse response;
 
	//business logic
	public String execute() {
		Locale locale = getServletResponse().getLocale();
		return "SUCCESS";
	}
 
	public void setServletResponse(HttpServletResponse response) {
		this.response = response;
	}
	public HttpServletResponse getServletResponse() {
		return this.response;
	}	
}

Both mechanism is getting the same HttpServletResponse object, but Struts 2 documentation is recommend to use the ServletResponseAware, see the reference below.